Visual Quantum Mechanics

Fluorescence Spectroscopy

STEP 1: Creating the Excited and Impurity state bands

Click on the "Create Excited State Band" button to the right of the energy
level diagram. An excited state band appears. Then click the "Create Impurity
State Band" button below, and an impurity state band appears below the excited
state band. The are the bands in the material that is used to coat the insides
of the fluorescent lamps.

STEP 2: Providing the Input Energy

Drag the "Input Energy" slider at the bottom left of the screen to increase
the input energy of the First Source to the infrared detector. Observe the
marker on the vertical scale of the energy level diagram rise to indicate the
increase in the impute energy. When the input energy is greater than the energy
of the excited state band. Click the "Turn on Lamp" button. The Mercury gas
in the diagram above begins to glow with a color corresponding to the input
spectrum energy. On the energy level diagram observe a transition from the
ground state to the excited state and then another from the excited to the
impurity state, and then from the impurity state to the ground state. The energy
corresponding to this last transition appears on the Output spectrum below
the energy level diagram and the lamp on the left of the screen begins to glow
with that color. The material of the coating in the cross sectional view below
the lamp also begins to glow.

STEP 3: Altering the energy bands

Click the "Edit Properties" button, and observe then click and drag the energy
bands on the energy level diagram. After adjusting the bands to a new value,
you may need to alter the input energy on the slider so that the input energy
is greater than the excited state band energy. Then click the "Turn on Lamp" button
to repeat the transitions.